Here is the situation (Alabama HS) NFHS Rules: Pitcher, in the windup with NO RUNNERS ON BASE hangs leg in the air, without any movement anywhere else (dead stop) for about 1-3 seconds. Next pitch may not hang at all. Next pitch while hanging leg pumps it up and down twice before delivery. But mainly just hangs leg for between 1 to 3 seconds (no joke....really that long). My reading of 6-1-2 is literal.. "After he starts his movement to pitch, he must continue the motion without INTERRUPTION or alteration.” Now, I'm not saying he cannot have a small pause, but here we have a complete stop.

If there were runners on base, it would be a balk. Under HS rules, anything that would be a balk with runners on base is an illegal pitch with the bases empty. I might overlook little stuff with the bases empty, but not this. I'd call the illegal pitch.